1. Field of the Invention
The present invention relates to a printing apparatus and a printing method in which a plurality of types of recording media are usable and to a storage medium in which a program code implementing the method is stored. The invention is also concerned with an information processing apparatus that transmits print data to effect a printing operation.
2. Description of the Related Art
A printing apparatus, such as a laser beam printer (hereinafter referred to as an “LBP”), forms a printing system when used in cooperation with an information processing apparatus, such as a computer. In the printing apparatus, when printing paper (hereinafter simply referred to as “paper”) is the recording medium, it is normally fed with the upper portion of the paper first.
There are some printing apparatus of the above type in which not only standard paper, but also envelopes or postcards, are usable. To perform a printing operation on an envelope by using some such apparatus, it is necessary to feed the envelope in such a manner that the unsealed end leads the sealed end in the direction of feeding. FIG. 1A is a schematic side view of a known LB P illustrating the feeding direction of an envelope to be printed by using the LBP. FIG. 1A shows an LBP 101, a feeding tray 102 on which paper to be fed is placed, an envelope 103 placed on the feeding tray 102, and a discharging tray 105 to which printed paper is discharged. An arrow 104 indicates the direction in which the envelope 103 placed on the feeding tray 102 is fed to the LBP 101.
FIG. 1B illustrates the envelope 103 shown in FIG. 1A as viewed from the top. The envelope 103 has an unsealed end 106 and a sealed end 107.
However, the following problems are encountered when feeding the envelope 103 in such a manner that the unsealed end 106 is placed forward of the sealed end 107 in relation to a printing mechanism (hereinafter referred to as a “print engine”) of a printing apparatus, such as an LBP. The incidence of paper jams, described below, is increased. The unsealed end 106 becomes stuck in one of the elements of the paper feeding mechanism, which hampers correct feeding of the envelope 103, thereby causing the envelope 103 to remain within the print engine. This inconveniences the user, wastes paper, and can lead to breakdown or early deterioration (shortening the life) of the print engine.
In order to solve the above problems, the following technique has been proposed. An envelope is fed in such a manner that the sealed end is located forward of the unsealed end, i.e., the envelope is turned 180 degrees from the known feeding direction, and a bit map image to be printed on the envelope is also turned 180 degrees. Printing processing accompanied by the above-mentioned paper feeding and image turning processing is hereinafter referred to as “reverse feeding and printing processing”. With reverse feeding and printing processing, the incidence of jams is reduced because the unsealed end of the envelope, which is more likely to be stuck in an element of the paper feeding mechanism, is oriented backward in the direction of feeding, and the sealed end, which is less likely to be stuck in an element of the paper feeding mechanism, is placed forward in the direction of feeding.
FIG. 2A illustrates the relationship between the orientation of an envelope and a bit map image according to, a technique prior to the advent of the reverse feeding and printing processing technique. The bit map image shown in FIG. 2A has been created for the case in which printing is performed by a printing apparatus (LBP) which feeds the envelope to the print engine from the unsealed end. FIG. 2A shows an envelope 202, a bit map image 201 to be printed on the envelope 202, a feeding direction 207 of the envelope 202 to the printing apparatus, a leading position 203 of the bit map image 201, and a trailing position 204 of the bit map image 201. The bit map image 201 is developed and stored in a memory (not shown) within the printing apparatus. A position 205 on the envelope 202 corresponds to the leading position 203 of the bit map image 201, and a position 206 corresponds to the trailing position 204 of the bit map image 201. The printing apparatus prints a visual image, corresponding to the bit map image 201 in the memory, in such a manner that the positions 203 and 204 of the bit map image 201 match the positions 205 and 206 of the envelope 202, respectively.
FIG. 2B illustrates the relationship between the orientation of an envelope and a bit map image according to the reverse feeding and printing processing technique. The bit map image has been created for the case in which printing is performed by a printing apparatus (LBP) which feeds the envelope to the print engine from the sealed end. FIG. 2B shows an envelope 212, a bit map image 211 to be printed on the envelope 212, a feeding direction 217 of the envelope 212 to the printing apparatus, a leading position 213 of the bit map image 211, and a trailing position 214 of the bit map image 211. The bit map image 211 is exactly the same as the image obtained by turning the counterpart 201 shown in FIG. 2A 180 degrees. A position 215 on the envelope 212 corresponds to the leading position 213 of the bit map image 211, and a position 216 corresponds to the trailing position 214 of the bit map image 211. The printing apparatus prints a visual image, corresponding to the bit map image 211 in the memory, in such a manner that the positions 213 and 214 of the bit map image 211 match the positions 215 and 216 of the envelope 212, respectively. In this manner, the reverse feeding and printing processing is implemented.
Known LBPs have a function by which a user can specify the paper type for use in printing, such as “A4”, “B5”, and “Envelope Kakugata No. 2” (Japanese standard), and can perform a printing operation in accordance with the specified type of paper. By using this function, the information concerning the designated paper type is converted into paper size information that is stored, together with paper type information, in a printing apparatus or an information processing apparatus. The paper size information is then used for printing processing.
Generally, the printing process used in the LBP is as follows. An electrostatic latent image is formed with a laser beam on a drum coated with a photosensitive material, and a coloring powder (toner), which is charged with a polarity opposite to the latent image, is attached to the drum. The latent image is transferred to a paper. A roller is then pressed against the paper to fix the image on the paper by heat and pressure. However, specific types of paper, such as that used in “Envelope Kakugata No. 2”, are thicker than standard printing paper, and envelopes are also double-structured to form a bag-like shape. Accordingly, the energy (or paper feeding rate) which would normally be sufficient to raise the temperature to fix the toner on standard paper does not increase the temperature sufficiently to fix the toner on such an envelope. In a conventional printing system, when using the above type of envelope, the user specifies that cardboard paper is being used in order to increase the heating amount to a level sufficient to fix toner on cardboard (hereinafter referred to as “cardboard mode fixing”).
The above type of printing system, however, requires a complicated operation, since the user is required to independently utilize a function of designating the type of paper and a function of performing a specific printing process, such as reverse feeding and printing processing and/or the cardboard mode fixing. More specifically, the user first specifies the type of paper, for example, “Envelope Kakugata No. 2”, then designates reverse feeding and printing processing, which requires the setting of the envelope in the direction opposite to that shown in FIGS. 1A and 1B on the feeding tray of the printing apparatus, and finally specifies cardboard mode fixing. If the above operations are erroneously performed or the orientation of paper is incorrectly set, printing cannot be performed correctly because the feeding direction has been wrongly set or an image has been insufficiently fixed, thereby wasting time and paper, or causing a breakdown or early deterioration (shortening the life) of the print engine due to paper jams.